Want to creep out your roommate or spouse? Buy them this lovely collection of Death Eater masks.

Finally, for the person you don't really like, you should definitely get them Umbridge's quill.

For that special Harry Potter fan in your life (the one who has read all the books) see below the spoilers for a few more suggestions.

Spoilerspaceifyouhaven'tfinishedHarryPotterandtheDeathlyHallows

Voldemort should have really checked the Internet before going through all the effort of tracking people down and breaking open tombstones. He would have found out that he could have gotten Dumbledore's wand online. Really, all he needed was a major credit card and a mailing address. But you can buy it and have an Elder Wand of your own (and then you can't tell anyone ever.)

Nah... skip the Elder Wand and get Draco's wand, which would of course, be more useful for a duel with Voldemort... an everyday situation we all frequently find ourselves in.

And Harry and Griphook would have found this Gryffindor sword rather desirable. This is the original one, right? It would really be useful for destroying all the horcruxes you have lying around the house.